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61.
Two new species of Naticidae ( Mollusca, Gastropoda) collected from the coast of China are described: Cryptonaitca huanghaien- s/s sp. nov. and Sinum vittatum sp. nov. The morphological characteristics between the new species were described and the related information was provided. The similarities and differences between the new species and related species were also compared and discussed. The new species Cryptonaitca huanghaiensis differed from Cryptonaitca hirasei and Cryptonaitca andoi in outer shape, operculum and radula. The new species Sinum vittatum is similar to Sinumjaponicum (Lischke, 1869), but the shell of the former is flat-elliptical in shape, spire very small, slightly convex. While the latter is flat-globular in shape, apex light brown in color, without a brown band on the body whorl. The comparison results revealed that Cryptonaitca huanghaiensis and Sinum vittatum were two new species from the coast of China. Specimens studied were obtained from collections in the Marine Biological Museum, Chinese Academy of Sciences.  相似文献   
62.
中国科学院海洋研究所建所70年来,在海洋贝类分类学研究领域取得了长足发展与进步,做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展,概述了取得的主要科研成果,分析了现代腹足类分类学研究的发展趋势以及面临的挑战,并对今后的发展提出了相应对策和建议。  相似文献   
63.
冰岛位于北大西洋北部地区,是对全球气候变化最为敏感的区域之一,对其周边海域古海洋环境的深入研究是全球气候变化研究的重要组成部分。海冰的大面积分布是该地区的显著特点之一,对全球气候系统产生较大的影响意义。此外,冰岛周边海域大量火山灰沉积,也为古海洋环境研究提供了可靠的年代资料。本文以冰岛为中心,回顾了冰岛周边海域末次冰消期以来古海洋环境及海冰研究的现状,探讨了该海域不同记录之间的差异,并通过分析末次冰消期以来古环境研究的不足,提出了相应的展望。  相似文献   
64.
东亚边缘海区浮游植物春华的纬向与年际变化   总被引:1,自引:1,他引:0  
Combined studies of latitudinal and interannual variations of annual phytoplankton bloom peak in East Asian marginal seas(17°–58°N, including the northern South China Sea(SCS), Kuroshio waters, the Sea of Japan and the Okhotsk Sea) are rarely. Based on satellite-retrieved ten-year(2003–2012) median timing of the annual Chlorophyll a concentration(Chl a) climax, here we report that this annual spring bloom peak generally delays from the SCS in January to the Okhotsk Sea in June at a rate of(21.20±2.86) km/d(decadal median±SD). Spring bloom is dominant feature of the phytoplankton annual cycle over these regions, except for the SCS which features winter bloom. The fluctuation of the annual peak timing is mainly within ±48 d departured from the decadal median peak date, therefore this period(the decadal median peak date ±48 d) is defined as annual spring bloom period. As sea surface temperature rises, earlier spring bloom peak timing but decreasing averaged Chl a biomass in the spring bloom period due to insufficient light is evident in the Okhotsk Sea from 2003 to 2012. For the rest of three study domains, there are no significant interannual variance trend of the peak timing and the averaged Chl a biomass. Furthermore this change of spring phytoplankton bloom timing and magnitude in the Okhotsk Sea challenges previous prediction that ocean warming would enhance algal productivity at high latitudes.  相似文献   
65.
The bioacoustics of upper waters of the Black Sea, the Sea of Marmara, and the Mediterranean Sea were studied in October 1999 with an echosounder with 120 and 200 kHz dual‐beam transducers. Net tows were taken to ground‐truth the acoustic volume backscattering. A forward solution was applied to determine significant scatterers of the three seas with regard to detection limits of the frequencies and background noise measured in each sea. The noise was 4 dB higher in the Sea of Marmara than in the other two seas. 200 kHz data showed significant correlation between measured and calculated volume backscattering strength, and density (biomass and abundance) of the taxa. Large‐sized copepods and chaetognaths in the Black Sea, Aurelia, Beroe, chaetognaths and large‐sized and abundant appendicularians in the Sea of Marmara, and fish larvae in the Mediterranean Sea contributed most to the volume backscattering.  相似文献   
66.
In an attempt to contribute to efforts for a robust and effective numerical tool addressing ship motion in astern seas, this paper presents the development of a coupled non-linear 6-DOF model with frequency dependent coefficients, incorporating memory effects and random waves. A new axes system that allows straightforward combination between seakeeping and manoeuvring, whilst accounting for extreme motions, is proposed. Validation of the numerical model with the results of benchmark tests commissioned by ITTC's Specialist Group on Stability demonstrated qualitative, yet not fully satisfactory agreement between numerical and experimental results in line with other predictive tools. The numerical results indicate that the inclusion of frequency coefficients definitely affects the accuracy of the predictions. In order to enhance further the numerical model and obtain useful information on motion coupling, extensive captive and free running model tests were carried out. Good agreement with the experimental results was achieved. These studies provide convincing evidence of the capability of the developed numerical model to predict the dangerous conditions that a ship could encounter in extreme astern seas. As a result, it could offer new insights towards establishing relationships linking ship behaviour to design, environmental and operational parameters.  相似文献   
67.
The Japanese government is committed to resuming sustainable commercial whaling, both on the high seas and along the Japanese coastline. To this end scientific whaling programs are supported with public money and the byproducts of the catch are distributed to the public and utilized in a variety of ways. Here we review the policies which govern how these byproducts are disseminated within Japan, as well as how the population as a whole makes use of whale resources. Possibilities for the future, if and when the international moratorium on commercial whaling ends, are also discussed.  相似文献   
68.
三沙湾海域沉积物中甲藻休眠孢囊的初步研究   总被引:6,自引:2,他引:6  
李超  蓝东兆  方琦  顾海峰  陈晨  王检国 《台湾海峡》2003,22(1):38-45,T001
通过对福建三沙湾海域50个站位海底沉积物进行研究,共发现9属20种甲藻休眠孢囊。其中,有毒种类2种:Alexandrium minutun、A.tamarense,有害种类4种:Alexandrium affine、Gonyaulax spinifera、Lingulodinium polyedraum、Scripp-siella trochoidea。文中对孢囊的形态与丰度、分布特征进行了初步研究。  相似文献   
69.
福建三沙湾浮性鱼卵和仔、稚鱼的分布   总被引:6,自引:1,他引:6  
戴燕玉 《台湾海峡》2006,25(2):256-261
本文根据1990年2~11月在三沙湾海域分别进行4个季节调查的资料,对三沙湾鱼卵和仔、稚鱼的种类组成、丰度和主要种类的分布进行研究和探讨.结果表明,本海区共出现鱼卵和仔、稚鱼26种,分别隶属于17科22属.在数量上,鱼卵最高值出现在春季(5月),其中鱼卵丰度较高的种类是真鲷、带鱼、鲾和康氏小公鱼等种类.仔稚鱼以夏季丰度最高,并以鰕虎鱼丰度(71.8%)最高.在分布上,鱼卵的丰度以三都岛东北部和东吾洋海域最高,仔稚鱼以三都岛东部最为密集.这表明本海区的鱼类的主要产卵季节是春季和夏季.其数量、分布与水温及桡足类的分布关系密切.  相似文献   
70.
基于多星融合高度计数据的中国海波浪能资源评估   总被引:4,自引:2,他引:2  
Wave energy resources are abundant in both offshore and nearshore areas of the China's seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth in offshore waters of China, a parameterized wave power density model that considers the effects of the water depth is introduced to improve the calculating accuracy of the wave power density. Second, wave heights and wind speeds on the surface of the China's seas are retrieved from an AVISO multi-satellite altimeter data set for the period from 2009 to 2013. Three mean wave period inversion models are developed and used to calculate the wave energy period. Third, a practical application value for developing the wave energy is analyzed based on buoy data. Finally, the wave power density is then calculated using the wave field data. Using the distribution of wave power density, the energy level frequency, the time variability indexes, the total wave energy and the distribution of total wave energy density according to a wave state, the offshore wave energy in the China's seas is assessed. The results show that the areas of abundant and stable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, southeast of Taiwan in the China's seas; the wave power density values in these areas are approximately 14.0–18.5 k W/m. The wave energy in the China's seas presents obvious seasonal variations and optimal seasons for a wave energy utilization are in winter and autumn. Except for very coastal waters, in other sea areas in the China's seas, the energy is primarily from the wave state with 0.5 m≤H s≤4 m, 4 s≤T e≤10 s where H s is a significant wave height and T e is an energy period; within this wave state, the wave energy accounts for 80% above of the total wave energy. This characteristic is advantageous to designing wave energy convertors(WECs). The practical application value of the wave energy is higher which can be as an effective supplement for an energy consumption in some areas. The above results are consistent with the wave model which indicates fully that this new microwave remote sensing method altimeter is effective and feasible for the wave energy assessment.  相似文献   
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